Transformer



J. C. HOWES July 22, 1930.

TRANSFORMER Filed May a. 1929 Inventor: John C.Howes. by M His Attorney.

Patentedlulyzzlfio UNITED sures Jon 0. nowls, or

PATENT OFFICE rmsrmn, AmOIOl IO Om m column, A CORPORATION OI m You 7rmsronm a umm 11.4 m a, 1m. mm I0.

My invention relates to transformers and more particularly to clam ingmeans for transformer cores of the 'stributed type. In the distributedtype of transformer core,

there is a central leg surrounded by the windings. The ends of thisWinding leg are connected by end okes to three or more outer legsdistribut outside of the windings and providing return paths for themagnetic core flux. It is common Sractice, of course, to

form the core legs an yokes of thin superposed laminations which areinsulated from each other to prevent excessive edd currents, the wholecore structure being ound together into a rigid unit by suitable clamps.The general object of the invention is to provide an improved form ofclamping structure for a transformer core of the distributed Theinvention with its various objects and advantages will be betterunderstood from the following description taken in connection with theaccompanying drawing in which Fig. 1 is a pers ctive view of adistributed core type trans ormer provided with a core clampin structureconstructed and applied in accordance with the invention; Fig. 2 is anenlarged perspective view of art of the core clamping structure shown inig. 1, and

Figs. 3 and 4 are enlarged perspective views of details of the clampingstructure.

Like reference characters indicate similar parts in the differentfigures of the drawing.

The invention will be explained in connection with the transformer shownin Fig. 1

which has a distributed type magnetic core with a central winding leg 10surrounded by the windings 11 and with its ends connected by four outercore arts each including an outer core leg 12 an a pair of end yokes 13.

The laminations of eac of these outer core parts are compressed and clamed tlghtly together between two clamps 14 w lch extend slightly be andthe yokes 13 at the ends of the core w ere they are secured in place bybolts 15.

Each of the clamps 14 is formed of a single piece of suitable metal suchas wrought or malleable iron and includes a strai ht intermediatesection 16 with integral en sections 17 extending at ri ht angles fromthe ends of the section 16. ne face of the clamp is a lane flat surfaceand the other face has on 'tudinal strengthening ribs 18.

o of the clamps 14 are applied to the two opposite faces of each of theouter core arts, the intermediate sect-ions 16 of the c amps lying alongthe opposite faces of the outer core leg 12 and t e end sections 17 ofthe clamps lying along the opposite faces of the two end yokes 13. Thetwo clamps are applied with their plane flat surfaces against the outercore part which is between them. The outer edges of the end sections 17of the clamps extend slightly beyond the end yokes 13 and have theiropenings for bolts 15 which secure the clamps in place and compress thecore leg and yokes between them. Each outer core part with its pair ofclamps is thus a strong rigid structure.

The several parts of the core and the clamps are further securedtogether as a single strong rigid structure by interlocked jointsbetween the inner ends of the clamps on each outer core part and theinner ends of the adjacent clamps on the adjacent outer core parts. Theinner end of each end section 17 of each clamp is formed to provide ahook 19 and an edge portion 20, the edge portion 20 being displaced oroffset from the plane face of the clam next to the core to provide spacebetween this ofiset edge and the core for a hook 19 of the adjacentclamp. At each joint, the hook 19 of one clamp and the ofi'set edge 20of the other clamp are at the inner edges of the clamps whlle the offsetedge 20 of the first clamp and the hook 19 of the second clamp are attheir outer edges. Thus at each joint the hook of each clamp is arrangedto engage the offset edge of the other clamp, the clamps beingeffectively secured together but being pivotall connected and entirelfree to move angular y with respect to eac other about their connectingjoints.

Two clamps may be easily assembled or disassembled when the anglebetween them is small as is apparent from Fig. 3 in which one of thejoints is shown with the adjacent parts of the two clam s sli htlyseparated. After assembly with t e 0 set edges 20 of 100 each clampclose to the bases of the hooks 19 of the other clamp, the clamps areopened out to a larger angle and become securely locked together as isapparent from Figs. 2 and 4. Two of these pivotally interlocke clampsare placed in the angle between each two adjacent outer core parts asshown in Fig. 1 and the two clamps on each face of each outer core artare secured in place by the bolts 15.

he clamps thus bind the entire core securely to ether.

osses 21 for supporting the transformer leads 22 and for engaging thetransformer supporting rods 23 may be formed integrally with the clampsif desired. If the hooks 19 and offset edges 20 of each clamp arearranged as shown in Fig. 2 so that the hook at one end of each clamp isat its outer edge and the hook at the other end of the clamp is at itsinner edge, then all the clamps may be exactly alike.

In the commercial production of transformers, it is not practicable toassemble the core laminations with such precision that all the anglesbetween the outer core parts will be exactly the same. The pivotallyinterlocked clamps which have been described, however, adjust themselvesreadily to different angles throughout a wide ran e. A further advantageof the invention is that the entire clamping structure comprises veryfew parts and these few partsJnay be very .easily and quickly assembled.

The invention has been explained by illustrating and describing aspecific form thereof but it will be apparent that various changes maybe made without departin from the scope of the invention as define inthe appended claims.

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is:

1. A transformer including a magnetic core having a winding leg and aplurality of outer core parts connecting the ends of said winding leg,and two core clamps secured respectively to two of said outer coreparts, said core clamps being pivotally interlocked.

2. A transformer including a magnetic core having a winding leg and aplurality of outer core legs connected by yokes to the ends of saidwinding leg, and a core clamp secured to each face of each of said outerlegs and its yokes, each of said clamps being pivotally interlocked witha clamp on an ad acent outer core leg and its yokes.

3. A transformer including a magnetic core having a winding leg and aplurality of outer core parts connecting the ends of said winding leg,and two core clamps secured res ectively to two of said outer coreparts, eac clamp having an inner end formed with a hook and an edgeportion, the hook of each clamp engaging the edge portion of an adjacentclamp.

4. A transformer including a ma etic core having a winding leg and aplura ty of outer core parts connecting the ends of said winding leg,and two core clamps secured respectively to two of said outer core arts,each clamp havi an inner end forme with a hook and an 0 set edgeportion, the book of each clamfi engaging the offset edge portion of ana jacent clam 5. A transformer incfuding a ma etic core having a windingleg and a plura ity of outer core legs connected by yokes to the ends ofsaid winding leg, and a core clamp secured to each face of each of saidouter legs and its yokes, each of said clamps having an intermediatesection on its outer core leg and two inte a1 end sections on its yokes,the inner end 0 each of the end sections of each clamp being formed witha hook and an offset e ge portion, and each of said hooks engaging theoffset edge portion of an adjacent clamp.

In witness whereof I have hereunto set my hand this first da of Ma 1929.

J OHN HOWES.

